Heat‐Dissipation Design and 3D Printing of Ternary Silver Chalcogenide‐Based Thermoelectric Legs for Enhancing Power Generation Performance

Abstract Thermoelectric devices have received significant attention because of their potential for sustainable energy recovery. In these devices, a thermal design that optimizes heat transfer and dissipation is crucial for maximizing the power output. Heat dissipation generally requires external active or passive cooling devices, which often suffer from inevitable heat loss and heavy systems. Herein, the design of heat‐sink integrated thermoelectric legs is proposed to enhance heat dissipation without external cooling devices, realized by finite element model simulation and 3D printing of ternary silver chalcogenide‐based thermoelectric materials. Owing to the self‐induced surface charges of the synthesized AgBiSe2 (n‐type) and AgSbTe2 (p‐type) particles, these particle‐based colloidal inks exhibited high viscoelasticity, which enables the creation of complex heat‐dissipation architectures via 3D printing. Power generators made from 3D‐printed heat‐dissipating legs exhibit higher temperature differences and output power than traditional cuboids, offering a new strategy for enhancing thermoelectric power generation.


Figure S1 .
Figure S1.Crystal structure diagrams of cubic phase for a) AgBiSe2 and b) AgSbTe2 visualized using VESTA software.

Figure S2 .
Figure S2.The percentage of exposed surface area, temperature difference, output voltage, electrical resistance, and output power of different shapes compared to those for a cuboid shaped leg using AgSbTe2.

Figure S5 .
Figure S5.Schematic representation of the optimization process for the TEG shape exhibiting the highest temperature distribution through integration of heat-dissipation design and optimization of n-type and p-type TE leg cross-sectional area ratio.

Figure S6 .
Figure S6.Output power percentage of each TEG shape compared to that of the cuboid design with unoptimized cross-sectional area ratio.

Figure S7 .
Figure S7.Photographs showing the time-dependent dispersibility of a) AgBiSe2 and b) AgSbTe2 TE inks.

Figure S9 .
Figure S9.Electrophoretic light scattering (DLS) size of the a) AgBiSe2 and b) AgSbTe2 particles dispersed in NMF.

Figure S14 .
Figure S14.OM images of the a,b) as-printed and c,d) sintered TE filaments.

Figure S15 .
Figure S15.Diameters of the 3D-printed TE filaments versus printing speed for different dispensing pressures using a nozzle with an inner diameter of 510 µm.

Figure S16 .
Figure S16.Photographs of bridging TE filaments dependent on the diameters of the filaments of a) 240 µm, b) 340 µm, c) 410 µm, d) 510 µm and e) 610 µm and block-to-block distance between two graphite blocks of (i) 3 mm, (ii) 4 mm, (iii) 5 mm, (iv) 6 mm and (v) 7 mm.The red lines indicate the filaments that start to sag.

Figure S17 .
Figure S17.Densities and relative densities of the 3D-printed a) AgBiSe2 and b) AgSbTe2 samples depending on the sintering time.

Figure S18 .
Figure S18.XRD patterns of 3D-printed a) AgBiSe2 and b) AgSbTe2 samples.Enlarged XRD patterns of 3D-printed c) AgBiSe2 and d) AgSbTe2 samples depending on the sintering time.

Figure S26 .
Figure S26.Comparison of the compressive strength values among the 3D-printed ternary Ag chalcogenide TE samples and the reported conventional bulk TE samples.

Figure S27 .
Figure S27.Photographs of 3D-printed cuboid a) AgBiSe2 and b) AgSbTe2 through in-plane and cross-plane printing directions.Compressive stress-strain curve of the 3D-printed c) AgBiSe2 and d) AgSbTe2 samples to compare in-plane and cross-plane printing directions.